Intracellular recordings from neurones in rat cerebral cortex during hypoxia.

Neurones in rat hippocampal cortex were exposed to hypoxia while their membrane properties and responses to different kinds of stimuli were recorded with an intracellular electrode. The initial changes consisted of a small depolarization followed by a hyperpolarization. Following these early events the neurones lost their membrane potential through a large depolarization. Similar changes were observed in neurones where the Na/K-ATPase was blocked by ouabain. Responses to direct application of the transmitters GABA and glutamate, which was lost at this point, were restored by passive reestablishment of the membrane potential with current through the intracellular electrode.